Collapsible tap.



B. F. RINDFLEISCH.

COLLAPSIBLE TAP.

APPLICATION FILED MAR. 25. 1916.

- m1 %,9M, Patented Feb.6,1917.

2 SHEETS-SHEET 1.

B. F. RINDFLEISCH.

COLLAPSIBLE TAP. APPLICATION FILED MAR. 25. 191's.

Patented. Feb; 6,

2 SHEETSSHEET 2.

MD STATES PATENT BENJAMIN F. RINDIIELEISCH, 0F CLEVELAND, OHIO, ASSIGNOR, BY MESNE ASSIGN- MEETS, TO THE NATIONAL-ACME COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

- COLLAPSIBLE TAP.

Specification of Letters Patent.

Patented Feb. 6, llgjl'tu Application filed March 25, 1916. Serial No. $36,562.

in taps, and more particularly to that class thereof known as collapsible taps, the obect of the invention being to provide a tap of this character which is adjustable to thread work of varying diameters, and in which the cutters or chasers will be automatically released from contact with the threads of the work after the tap has cut its required length, and which tap can be removed from the work without the necesr sity of reversing or backing out of the threaded piece. y

A further object of the invention is the provision of a tap of the character specified in which the length of the tapping operation of which the tap is capable is not limited by the length of the chasers or cutting portions, but which may be used for tapping to a depth many times the length of the cutters and in places where it would be inconvenient or impossible to use the ordinary form of tap.

A further object of the invention is the provision of a tap of the character specified which may be used for right or left-hand threading without the necessity of changing the construction of the tap operating mechanism, and in which all the working parts thereof may be hardened and ground without materially increasing the cost of manufacture, and the cutter blades or chasers of which are extremely simple in construction and inexpensive to manufacture.

In the drawings accompanying and formiing part of this specification, Figure 1 is a side view of my improved tap showing the *same assembled for use, with the cutters or chasers in their advanced position; Fig. 2 is an end view of Fig. 1, looking in the direction of the arrows; Figs. 3, 4, 5 and 6 are sectional views taken respectively on the lines 3-3, H, 55 and 66, Fig. 1, looking in the directions indicated by the arrows in Fig. 1; Fig. 7 is a sectional view taken on line 77, Fig. 9; Fig. 8 is a perspective view of one of the chasers or cutters detached from the body of the tap; F ig. t) is a side view similar to Fig. 1, but show mg the cutters withdrawn; Fig. 10 is a longitudinal section of the tap as shown in Fig. 9; Fig. 11 is a longitudinal section of the tap with the chasers in advanced position as shown in Fig. l; and Fig. 12 is a sectional view showing a modified form of core member or chaser adjusting means.

Similar characters of reference indicate corresponding parts in the different figures of the drawings.

1 am aware there are a number of taps on the market that are known as collapsible taps, but in all of those forms with which ll am familiar there are many disadvantages in the use thereof which it is the object of this improvement to overcome. For instance, with all other forms of taps with which I am familiar the depth that can be tapped is limited by the length of the chaser or cutter blade, for the reason that the mechanism for operating the tap is so bulky that the diameter of the body that houses such mechanism is much greater than the cutting size of the chasers, and therefore it is impossible to use them to cut or tap to any great depth or in the bottom of a deep hole of approximately the same diameter as the portion required to be threaded; whereas with the present improvement there is no limit of depth to which the work may be tapped, it being only necessary to increase the length of shank, which is in no way detrimental to the operation of the tap, since the chaser blades are supported throughout their entire length and operated by a center portion, and as the extreme diameter is the cutting size of the tap it is possible to use it in a great many places where it would be impossible to use other forms of taps.

In the form shown in the drawings, this improved tap comprises a body or head 2, in the front face of which are milled a plurality of radial slots 3 of the required depth andwidth to accommodate the chasers or cutter blades 4, four of which are shown herein, a disk or plate 5 being secured to the front face of the body 2 by means of screws or in any other suitable manner to retain the cutter blades within the slots 3.

Through the center of the body 2, lengthwise thereof, is bored a hole large enough to permit the passage therethrough of the shank portion 6 of a core member, the front portion of which core member is formed with a plurality of flattened portions, as 7,

-four being shown in the present instance,

one for each cutter blade, for the purpose hereinafter described, the front end of this core member being cylindrically formed and projecting through the plate 5. The front portion of the central bore of the body 2 is of larger diameter, as at 8, to provide a space for housing a spring 9 having one end thereof bearing against the corners of the flattened portions 7 of the core member and its opposite end against the bottom wall of the enlarged bore 8. The body portion 2 is also provided with lengthwise extending bores 10, one for each cutter blade, each of these bores having a portion of small diameter at its inner end adjacent the slot 3 for receiving a tripping pin 12 the end of which projects into a V-shaped recess 23 formed in the end of the cutter blade, the next adjacent portion of the bore 10 being of larger diameter so as to provide a shoulder against which the head of said pin 12 abuts and also to provide a chamber for housing a spring 13 which exerts its pressure against the head of said pin 12, the opposite end of the spring bearing against a set screw 11, which is threaded into a third portion of said'bore 10 of still larger diameter. In the rear face of the body 2 are secured a pair of driving pins 14, the purpose of which will be hereinaftermore fully explained.

The shank of the tap is provided with a hub portion 15 having in the front face thereof a central bore adapted to receive a so-called tripping sleeve dog 16, which is provided around its circumference with a groove 17 and at one end-with a flange 18 adapted to abut against the face of said hub portion 15 and having a central bore of suflicient size to permit passage of the end of the shank 6 of the core member hereinbefore described, the tripping dog 16 being removably secured to said shank portion 6 by means of a pin 19. The hub portion 15 is provided with a pair of threaded radial openings or bores adapted to receive binding screws 20 the ends of which project into the circumferential groove 17 of the tripping sleeve dog and hold the same within the bore of the hub portion 15 against rotation. The flange of the tripping sleeve dog is cut away at opposite sides thereof as shown at 21, Figs. 5 and 7, to leave two portions which act as stop members against which the driving pins 14 of the tap body abut at the proper time for limiting the rotation of the body relatively to the hub portion 15. The front face of the hub portion 15 is also provided with a pair of radial recesses or slots 22 with which the driving pins 14 co6perate for setting the tap in operative position, as will be hereinafter more fully explained.

The tap is assembled as shown in Figs. 9 and 10, that is to say the chasers or cutter blades are placed within the slots 3 of the body and the core member inserted through the central bore of said body 2 with the spring 9 encircling the shank portion 6 thereof, the flat portions 7 of the core member being parallel with the backs of the cutters 4 The end plate or disk 5 is then secured to the front face of the body 2 so as to retain the core member in place against the action of the spring 9, whereupon the tripping pins 12 are dropped into the bores 10 of the body, the springs 13 placed within the bores 10, and the set screws 11 screwed into the ends of such bores so as to bear against the ends of the springs 13 and cause them to exert their pressure on the pins 12 to hold the latter firmly in the recesses 23 in the ends of the cutter blades or chasers. The end of the shank portion 6 is then placed in the bore of the tripping sleeve dog 16 and secured therein by means of the pin 19, whereupon the tripping dog is placed within the bore of the hub portion 15and the binding screws 20 set tightly so as to project into the groove 17 of the tripping member 16 and hold the same against rotation. The parts are thus in the position shown in section in Fig. 10. In other words, the driving pins 14 are withdrawn from the slots 22 in the hub portion 15 and are in contact with the stop members 21 and the flat sides of the portion '7 of the core mom-- ber are in contact with the backs of the cutters or chasers, so that the cutters are in their withdrawn position and are locked in such position by means of the pins 12 projecting into the V-shaped recesses 23 under pressure of the springs 13.

When it is desired to set the tap into position to thread work which calls for the setting of the tap to its greatest diameter, the body 2 is turned relatively to the hub portion 15, by means of a removable handle 24, until the driving pins 14 are brought into position so that the pressure of the spring9 will force the body 2 backward so that the pins 14 will enter the recesses 22 in the hub portion 15. At the same time the body has been rotated with relation to the core member so that the corners of the flat portions 7 thereof engage the backs of the chasers or cutters and force them outwardly and hold them in such position, the V- shaped slots 23 in the cutter blades permitting the pins 12 to be forced back against the action of the springs 13 until the ends of such pins are almost withdrawn from said recesses 23, the pressure of the springs 13 against the pins causing the opposite ends of the cutters to bear firmly againstthe disk or plate 5.

In order to adjust the tap to cut any diameter'ofwork ranging from its smallest diameter, to wit, the diameter which it is capable of cutting when the chasers are in their withdrawn position as shown in Figs. 9 and 10, to its largest diameter, or the diameter which it is capable of cutting when the chasers are projected out to their full capacity as shown in Figs. 1 and 11, it is only necessary to loosen the adjusting binding screws 20 which project through the hub 15 into the groove 17 of the sleeve 16 and by means of the slot 26, (see Fig. 2), in the front end of the core member revolve or twist the same in either direction, whereby the relation between corners of the fiat portions 7 of the core member with the backs of the chasers or cutters is changed, so that the cutters, as stated, may be set to cut any diameter of work Within the limits named above.

The modified form of core'member shown in Fig. 12 will permit of a very much greater range of diameters to be threaded. For instance, if the diameter of the work tobe threaded is greater than is possible for the tap to reach when the chasers are positioned by a core member having flat sides, the extent to which the cutters may be forced outwardly may be very much increased by providing a core member having some such form as shown in Fig. 12, whereby when the body 2 is rotated relatively to said core' member the cutters or chasers will ride or cam on the projecting portions at the corners of this core member.

'Invthe operation of this improved tap, when the tapping operation is finished and the travel of the turret is stopped the tap is automatically released from the work, be-

cause of the fact that when the travel of the turret ceases the tap is drawn forward by reason of its engagement with the work, whereby the spring 9 is compressed and the continued rotation of the tap with the work releases the driving pins 14 from the slots 22 in the hub portion 15 and brings the driving pins into contact with the parts 21 ofthe flange of the tripping sleeve dog, this rotation of the tap having turned it relatively to the core member so that the flat portions 7 of the latter are parallel with the backs of the chasers, whereupon the springs'13 cause the ends of the pins 12 bearing on the side of the slots or recesses 23 in the chasers to force such chasers inwardly, in other words withdraw'the same from the work.

It will be understood, of course, that the various details of construction may be more or less varied without departing from the spirit or scope of this improvement. For instance, while I have shownherein a tap comprising only four cutting portions and a corresponding number of flat surfaces on the core member, Ido not desire to confine myself to these details, as the number of cutting members and corresponding fiat portions may be increased or decreased as found most desirable in practice.

It will thus be observed that I have provided an improved tap which is adjustable to any diameter within certain limits, and which is automatically released from the work after the tapping operation is completed, and without the necessity of reversing or backing out the threaded piece. It will also be observed that this improved tap can be used for right or left-hand threading without necessitating any change whatever in the mechanism, as it is only necessary to make the chasers either right or left hand and adjusting the core member to suit. It will also be seen that by reason of the construction of the tap access is afforded to all the working parts of the tap so that they can be hardened and ground without materially increasing the cost of manufacture, while the mechanism is so protected when the tap is in use that it is impossible for chips to interfere with the proper operation thereof.

I claim as my invention:

1. A collapsible tap comprising a body, one or more radially shiftable cutters .car-

-ried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable together and axially shiftable one relatively to the other thereby to release such body and hub-for independent rotary movement, and means secured to the hub and extending into the body for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap.

2. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable and axially shiftable one relatively to the other, means secured to the hub and extending into the body for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap, and means for locking the body and hub together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of said body.

3. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable and axially shiftable one relatively to the other, means secured to the hub and extending into the body for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap,

means for locking the body and hub to gether for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of said body, and means for limiting the rotation of such body.

4;. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter'than the body, said body and hub being rotatable and axially shiftable one relatively to the other, means secured to the hub and extending into. the body for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap, means for locking the body and hub together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of said body, and means for limiting the rotation of such body said means adjustable relatively to the hub.

5. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable together and axially shiftable one relatively to the other thereby to release such body and hub for independent rotary movement, means secured to the hub and extending into the body for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap, and adjustable means located between the hub and the body for limiting the rotary movement of the body independently of the hub.

6. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable together and axially shiftable one relatively to the other thereby to release such body and hub for independent rotary movement, means secured to the hub and extending into the body for shifting the cutters relatively to the body, the-diameter of the cutters being greater than any other part of the tap, and adjustable means located between the hub and the body for limiting the rotary movement of the body independently of the hub, said means comprising a pair of stops and a pair of stop pins.

7. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of. no greater diameter than the body, said body and hub being rotatable together and axially shiftable one relatively to the other thereby to release such body and hub for independent rotary movement, and means secured to the hub and extending into the body and having a plurality of relatively fiat cornerformed faces for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap.

8. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable and axially shiftable one relatively to the other, means secured to the hub and extending into the body and having a plurality of relatively flat corner-formed faces for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap, means for locking the body and hub together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of said body and means for limiting the rotation of such body, said means adjustable relatively to the hub.

9. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, said body and hub being rotatable together and axially shiftable one relatively to the other thereby to release such body and hub for independent rotary movement, a core member secured to the hub and extending into the body and having a plurality of relatively fiat corner-formed faces for shifting the cutters relatively to the body, the diameter of the cutters being greater than any other part of the tap, and means for securing the core member in different rotatable positions relatively to the body thereby to change the setting of the cutters.

10. A collapsible tap comprising a body, one or more radially shiftable cutters carried thereby, a shank having a hub of no greater diameter than the body, being rotatable togethervand axially shiftable one relatively to the other thereby to release such body and hub for independent rotary movement, a core member secured to the hub and extending into the body and having a plurality of relatively flat cornerformed faces for shifting the cutters relatively to the body, the diameter of the out ters being greater than'any other part of the tap, means for securing the core member in different rotatable positions relatively to the body thereby to change the setting of the cutters, and means for limiting the rotary movement of said body and hub relatively to each other.

11. A collapsible tap comprising a shankhaving a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and said body and hub.

having a plurality of relatively flat corner' formed faces for shifting the cutters on the rotation of the body relatively to the core member, means for maintaining the body and hub in juxtaposition, means carried between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body.

12. A collapsible tap comprising a shank having a hub, an adjustable core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of relatively flat corner-formed faces for shifting the out ters on the rotation of the body relatively to the core member, a spring for maintaining the body and hub in juxtaposition, means carried between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body.

13. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of relatively fiat cornerformed faces for shifting the cutters on the rotation of the body relatively to the core member, a spring for maintaining the body and hub in juxtaposition, means carried between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, and means between. the meeting faces of said body and hub for stopping the rotation of said body independently of the hub.

14. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of relatively flat corner-formed faces for shifting the cutters on the rotation of the body relatively to the core member, means for maintaining the body and hub in juxtaposition, means carried between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, and spring-pressed means carried by the body for locking said cutters Within the body.

' 15. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of relatively flat cornerformed faces for shifting the cutters on the rotation ofthe body relatively to the core member, means for maintaining the body and hub in juxtaposition, and means carried between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifiing of the body to permit the independent rotation of such body and adjustable relatively to the hub to limit the independent rotatable movement of the body.

16. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed fiat cutter-engaging faces for shifting the cutters on the rotation of the body relatively to the core member, a spring located on said core memberand housed within said body for maintaining the body and hub in j uxtaposition, means including a pin located between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, and means between the meeting faces of said body and hub for stopping the rotation of the body independently of the hub.

17. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a. body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat dependent rotation of such body, and ad' justable means between the meeting faces of said body and hub for stopping the rotation of the body independently of the hub.

18. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed fiat cutter-engaging faces for shifting the cutters on the rotation of the body relatively to the core member, a spring located on said core member and housed within said body for maintaining the body and hub in juxtaposition, means including a pin located between the meeting faces of the hub and body for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, adjustable means between the meeting faces of said body and hub for stopping the rotation of the body independently of the hub, and spring-pressed means carried by the body for locking the cutters within the body.

19. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat cutter-engaging faces for shifting the cutters on the rotation of the body relatively to the core member, a spring located on said core member and housed within said body for maintaining the body and hub in juxtaposition, means including a pin located between the meeting faces of the hub and body for locking the hub and body together for rotation and adaptedto be released on the axial shifting of the body to permit the independent rotation of such body, adjustable means between the meeting faces of said body and hub for'stopping the rotation of the body independently of the hub, and spring-pressed means carried by the body for locking the cutters within the body, the diameter of the cutters being greater than any other part of the tap.

20. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat cutter-engaging faces for shifting the cutters on the rotation of the body relatively to the core member, a sprin g located on said core member and housed within said body for maintaining the body and hub in juxtaposition, means including a pin located between the meeting faces of the hub and body for locking the hub and body together for rotation' and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, adjustable means between the meeting faces of said body and hub for stopping the rotation of the body independently of the hub, and spring-pressed means carried by the body for locking the cutters within the body, said core member and hub being removably connected.

21. A collapsible tap comprising a shank having a hub, a core member secured to said ing the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, adjustable means between the meeting faces of said body and hub for stopping the rotation of the body independently of the hub, and spring-pressed means carried by the body for locking the cutters within the body, the diameter of the cutters being greater than any other part of the tap, said core member and hub being removably connected.

, 22. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat faces for shifting the cutters on the rotation of the body relatively to the core member, a spring for maintaining the body and hub in juxtaposition, and means comprising a slot and a pin carried one by the hub and the other by the body adjacent to the meeting faces thereof for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body.

23. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat faces for shifting the cutters on the rotation of the body relatively to the core member, a sprlng for maintaining th body and hub in juxtaposition, means comprising a slot and a pin carried one bv the hub and the other by the body adjacent to the meeting faces thereof for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to a a-ante having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a pluralityrof corner-formed fiat faces,

for-shifting the cutters on the rotation of the body relatively to the core member, a spring for maintaining the body and hub in juxtaposition, means comprising a slot and a pin carried one by the hub and the other by the body adjacent to the meeting faces thereof for locking the hub and body together for rotation and adapted to be released on the axial shifting of the body to permit the independent rotation of such body, and a stop located between the hub and body for limitingthe rotation of the body independently of the hub, said stop being adjustable relatively to the hub.

25. A collapsible tap comprising a shank having a hub, a core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member" and having a plurality of corner-formed flat faces for shifting the cutters on the rotation of thevbody relatively to the core member, a spring housed within said body for maintaining the body and hub in juxtaposition, means comprising a slot and a pin carried one by the hub and the other by the body adjacent to the meeting faces thereof for locking the hub and body together for rotation and adapted to be released on the axial shifting of the bodv to permit the independent rotation of such body, a stop located between the hub and the body for limiting the rotation of the body independently of the hub, said StOpzbGlIlg adjustable relatively to the hub, and spring-pressed means carried by the body for locking said cutters within the body.

, 26. A collapsible tap comprising a shank having a hub, an adjustable core member secured to said hub, a body axially shiftable on and rotatable relatively to said core member and having a plurality of radially shiftable cutters, means carried by said core member and having a plurality of corner-formed flat faces for shifting the cutters on the rotation of the body relatively to the core member, a spring housed within said body for maintaining the body and hub in juxtaposition, means comprising a slot and a pin carried one by the hub and the other by the body adjacent to the meeting faces thereof for locking the hub and body together for rotation and adapted to be released on the axial'shifting of the body to permit the independent rotation of such body, a stop located between the hub and the limiting the rotation of the body ently of the hub, said stop being adjustable relatively to the hub, and spring-pressed means carried by the body for locking said independcutters within the body, the diameter of the cutters being greater than any other part of the tap.

27 A collapsible tap comprising a shank having a hub of greater diameter than the shank, a body having substantially the same diameter as the hub, a plurality of radially shiftable cutters carried by the body and having greater diameter than the body and hub, a core member secured within the hub and rotatable therewith and projecting into said body and upon which the body is shiftable axially and having a plurality of cornerformed surfaces for engaging the cutters to radially shift them, a spring upon said core member and housed within the body forbody for be radially shifted by said core member into different positions, said body andcore being rotatable together and independently one of the other and also axially shiftable relatively to each other, and means for adjusting said parts thereby to permit the core member to hold the cutters in position at their extreme outward or inward positions or in a position therebetween.

29. A collapsible tap comprising a core member having a plurality of relatively flat and cornered surfaces, a body having a plurality of radially shiftable cutters adapted to be radially shifted by said core member into different positions, said body and core being rotatable together and independently one of the other and also axially shiftable relatively to each other, means for adjusting said parts thereby to permit the core member to hold the cutters in'position at their extreme outward or inward positions or in a position therebetween, and means for locking the body and core for rotary movement together.

30. A collapsible tap comprising a core member having a plurality of relatively flat and cornered surfaces, a body having a plurality of radially shiftable cutters adapted to be radially shifted by said core member into different positions, said body and core being rotatable together and independently one of the other and also axially shiftable relatively to each other, means for adjusting said parts thereby to permit the core member to hold the cutters in position at their extreme outward or inward positions or in a position therebetween, means for locking the body and core for rotary movement together, and means for limiting the independent rotary movement of the body and core relatively to each other.

31. A collapsible tap comprising a core member having a plurality of relatively flat -and cornered surfaces, a body having a plurality of radially shiftable cutters adapted to be radially shifted by said core member into different positions, said body and core being rotatable together and independently one of the other and also axially shiftable relatively to each other, means for adjusting said parts thereby to permit the core member to hold the cutters in position at their extreme outward or inward positions or in a position therebetween, means for locking the body and core for rotary movement together, and means for limiting the independent rotary movement of the body and core relatively to each other, said cutters having a diameter greater than any other part of the body.

32. A collapsible tap comprising a body, a plurality of removable cutters carried thereby, a shank having a hub provided with a central opening and a pair of radial threaded openings therein, a connecting member passing through said body, a removable sleeve attached to said connecting member and provided with a circumferential groove, said sleeve being adapted to be inserted into the central opening in said hub, a pair of binding screws passing through said threaded openings and coiiperating with said roove to secure said sleeve within said hub,

said body and shank being rotatable together and independently, and means carried by said connecting member for adjusting said cutters to varying diamete s upon rotation of the hub and body relatively to each other.

33. A collapsible tap comprising a body having a plurality of radial slots, a remov able cutter carried by each of said slots, a core having a cylindrical portion passing through said body' and also having flattened portions adapted to support said cutters in said slots, a spring housed within said body and exerting pressure lengthwise of said body and core, a shank to which said cylindrical portion is removably secured whereby the body and shank are rotatable together and independently, and cooperating means carried by said body and shank for limiting thle1 rotation of one independently of the ot er.

34. A collapsible tap comprising a body, a plurality of removable cutters carried by said body, a shank, cooperating means carried by said body and shank for adjusting said cutters to varying diameters, and means for locking said cutters in any of their adjusted positions, said means comprising spring-actuated pins carried by said body.

A collapsible tap comprising a body having a plurality of radial slots, a removable cutter carried by each of said slots and having a recess in one end thereof, a shank, cooperating means carried by said body and shank for reciprocating said cutters within said slots, and spring-actuated pins carried by said body and projecting into said reciesses for locking said cutters within said s ots.

36. A collapsible tap comprising a body having a plurality of radial slots, a removable cutter carried by each of said slots, a

shank, a core having a cylindrical portion passing through said body and removably secured to said shank and also having flattened portions adapted to normally support said cutters in said slots, a spring housed within said body and exerting pressure lengthwise of said body and core whereby said body and shank are held in contact with each other, means for separating said body and shank against the action of said spring and for rotating the body relatively to the shank, and means for limiting such inde' pendent rotation and comprising pins carried by one of said members and stops car'- ried by the other.

37. A collapsible tap comprising a body having a plurality of radial slots, a removable cutter carried by each of said slots, a shank, a core having a cylindrical portion passing through said body and removably secured to said shank and also having flattened portions within said body adapted to support said cutters in said slots, a spring housed within said body and exerting pressure lengthwise of said body and core whereby said body and shank are normally held in contact with each other, means for separating said body and shank against the action of said spring and for rotating the body relatively to the shank, and means for limiting such independent rotation and comprising pins carried by said body and stop members carried by said shank.

38. A collapsible tap comprising a body having a plurality of radial slots open at one end, a removable cutter carried by each of said slots, a removable disk for closing the ends of said slots, a shank, a core having a cylindrical portion passing through said body and removably secured to said shank and also having flattened portions within and exerting pressure lengthwise of said for locking said cutters Within said slots and body and core whereby said body and shank comprising spring-actuated pins carried by are held in contact With each other, means the body. 13*- for separating said body and shank against Signed at Cleveland, in the county of 5 the action of said spring and for rotating the Cuyahoga and State of Ohio, this 21st day body relatively to the shank, means for'limof March, 1916.

iting such independent rotation, and means BENJAMIN F. RINDFLEISCH, 

